Andy Murray explains why so few men outside of the top four seeds have been recently unable reach the semifinals of the majors. The top four men’s seeds—Murray, Novak Djokovic, David Ferrer, and Roger Federer—reached the semifinals at the Australian Open. Last year, the only men outside of the top four seeds to reach a Grand Slam semifinal were Tomas Berdych at the U.S. Open and Jo-Wilfried Tsonga at Wimbledon.

“I think the five-set matches are probably a good reason for that,” Murray said. “The longer the match goes on, someone like a Ferrer, for example, his game is so solid all the time, that to beat him over five sets, yesterday was a perfect example of that. [Nicolas] Almagro probably should have won [their quarterfinal].

For two, two-and-a-half sets he was the better player, but you need to be the better player for three out of five. There are way more upsets in tournaments that are best-of-three sets in the men’s just because you get off to a bad start and guys can get a quick win over you; whereas over best-of-five it often takes five hours sometimes to beat the top players in the world. It’s not easy.”